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Thread: LQ4 GT45 fall on face hard

  1. #1
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    LQ4 GT45 fall on face hard

    04 LQ4 yukon awd frame silverado reg cab transplant
    GT45, walbro 450, .600 lift springs, s deka 80lb,
    looking to get 8-11 psi
    Heres the issue i currently have the truck runs amazing while in park throttle is real quick ect but as soon as i put it in gear it starts to cut out or miss kinda and ill start to log a pass and it wont it will spit and sputter and eventully die, it will fire back up and do the same thing i guess i just cant figure out what setting im overlooking i thank you in advance for your time if you could please help. im not a tuner dont claim to be over the past two months ive read watched vids and asked for help i cant log a run bc it just wont run thanks again

    speed den _WLM_Revised_rev4_Map2bar1.hpt

  2. #2
    Advanced Tuner rabbs88's Avatar
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    Need to see a log

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    ok ill try to log one

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    Bad Deka 80 data.
    https://forum.hptuners.com/showthrea...l=1#post796064

    Make sure the data is setup for vacuum-referenced regulation. You should be running a referenced reg.

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    so do i need to do a return fuel set up to do a vac ref? i do have a vac ref reg but its just set up as a regulator set at 58

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    Senior Tuner edcmat-l1's Avatar
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    Need to have a fuel pressure gauge in the vehicle that you can see from the driver's seat.

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    i have that and i had it set up as a return fuel system with it adjusted to 58 with vac off when turned on went to 43.5 but still had this prob.. so do change it back to return set up from a 2000 silverado or keep it the returnless? if keep it returnless do i just run fuel line into reg on one side other side run to rails then a vac

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    Quote Originally Posted by ucepnut1 View Post
    i have that and i had it set up as a return fuel system with it adjusted to 58 with vac off when turned on went to 43.5 but still had this prob.. so do change it back to return set up from a 2000 silverado or keep it the returnless? if keep it returnless do i just run fuel line into reg on one side other side run to rails then a vac
    Id go back to the factory return regulator.
    What brand regulator do you have now? 58 to 43 is a substantial drop in pressure.

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    Quote Originally Posted by RDF1 View Post
    Id go back to the factory return regulator.
    What brand regulator do you have now? 58 to 43 is a substantial drop in pressure.
    Didn't we just go down this road a couple of weeks ago with a guy who said he was checking fuel pressure, but actually just tossed out some numbers that he thought were supposed to be right?

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    Quote Originally Posted by gametech View Post
    Didn't we just go down this road a couple of weeks ago with a guy who said he was checking fuel pressure, but actually just tossed out some numbers that he thought were supposed to be right?
    No Comment..

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    Quote Originally Posted by gametech View Post
    Didn't we just go down this road a couple of weeks ago with a guy who said he was checking fuel pressure, but actually just tossed out some numbers that he thought were supposed to be right?
    Good call. That was a different guy. This is the person who is running decapped injectors with Deka data, wrong fuel pressure, wrong bank assignment, and no followup on recommendations. It's easy to confuse the two.

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    this is why people just try and do it their selfs bc when you ask for help people like you that should be cool and help want to come on here and talk shit smh its pethetic.

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    Quote Originally Posted by SiriusC1024 View Post
    Good call. That was a different guy. This is the person who is running decapped injectors with Deka data, wrong fuel pressure, wrong bank assignment, and no followup on recommendations. It's easy to confuse the two.
    I know this is a different guy, although I had forgotten about giving up on him after he kept posting locked files. I just meant going down the same road of not being honest about checking the fuel pressure, but still expecting people to be able to help while giving bad info to us. Any time a person says 58psi (rounded to exact number), but then says 43.5psi (specific to .1psi) they are just making up bullshit they think it is supposed to be. They have not actually checked shit. I used to see this every day in the electronics world with voltage checks.

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    Quote Originally Posted by ucepnut1 View Post
    this is why people just try and do it their selfs bc when you ask for help people like you that should be cool and help want to come on here and talk shit smh its pethetic.
    You're not letting anyone help is the problem. Last post from me on the other thread pointing was left with no reply.

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    for one im being honest its a cheap fuel pressure reg and the needle on the damn thing bounces so yes non vac i set it at 58 and when i hooked vac it went down to 40 something but the gauge isnt very detailed and i was going to buy a better fpr tonight

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    i mustve not seen it for that is my bad.

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    Even a log that only shows key-on and crank-no-start can give a ton of useful data in trying to diagnose things.

    Knowing what you don't know is a very high skill level - and if you ask for help with the newbie entry-level basics but then take every suggestion as a criticism, you are never going to get any closer to being able to DIY your own stuff.
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    Funny how accounts marked as 'banned' are still able to log in and do stuff on the site, huh?

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    oh i didnt know ok ill post one thank you

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  20. #20
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    Quote Originally Posted by ucepnut1 View Post
    for one im being honest its a cheap fuel pressure reg and the needle on the damn thing bounces so yes non vac i set it at 58 and when i hooked vac it went down to 40 something but the gauge isnt very detailed and i was going to buy a better fpr tonight
    Now that people know what results you are getting from what type of equipment, they can give useful answers based on real diagnostic feedback. We can work with that.